Inserted blade cutter



unirse nizs'iin'riib LADE GUTTER iaxik P. Miller, Meadville, ifa.

Application ydimi-l 419,

y 2 lims.

Thisfinvention yrelates 'to inserted `blade 'cutters, fand 'will be found to be `in'the nature of an improvement on the construction lshown in vmy prior Patent No. 1319;?137, xissued July 2, 1929.

`Enmy `prior Apatent herein mentioned, 'andimore particularly -in that -formoi inventionishown on sheet l2 of the drawing therein, each inserted blade is engaged at one-side thereof `by a holding wedge Aandthe wedge'is, in turn, engaged at the base thereoiibyiataperedkey which, when driven endwise, exerts `an `outimard-iorce on the wedge and brings about binding engagement of the wedge Witlfrfthe associatedrblada However, in my prior patent, the Wedge 'has -a-radial dimension substantially less than the radial `dimension of the blade with the `result `that the wedge has pressure contact with but a minor portion of the blade. -By `reason of the position and *the linierijor radial Vdimension 1Vof 'the Wedge, as compared to the radial dimension of the blade, the Wedge actuating key -is located between the inner and outer edges of the blade and at all `positions of blade adjustment the blade-remains 1in restraining relation with the key, holding the key i in direct supporting engagement with -t-h'e Wedge and against lateral shifting. into the blade-receiving slot. i l W Also, in; my `fprior patent herein referred to, the

amount `of radial blade adjustment i-s limitedbe- 30 cause if the blade is vmoved out beyond the key,

the 'bladeloses restraining relation tothe key allowing-the key to shift out of supporting engagement with the wedge. For this reason, the amount ot blade material that may be used is .35 limitedand one ofthe features of this invention will be foundto reside inthe means by which the blade may be moved aradiallyoutward` beyond `the key without risking the slriift'ing rof ,the key out of supporting engagement with the wedge, thus allowing fa maximum ,use of4 the expensive metal from which the blade is made.

However, -there are caseswhere the wedge has a lrad-iai dimension approaching the corresponding dimension of the blade `and Where the blade is adjustable to a position Where it is no' vlonger in `restrain-ing rela-tion tothe associatedikey, with the result that the conditions accompanying the use of 'the ltool may cause ishifting or slipping 'of the key 'out lof Asuppoitirig engagement with lthe 0 wedge, in which event me useof me `miner must 15e-interrupted fior the vresend'ng df :tile blade.

vvith'aii appfriation for trie foregoing, the iriveiition forming 'the "subject "of this 'application 5 will be found to bein the 'naturejof a'n inserted (onza-ids) 1 blade cutter in which the "binding Wedge located at one sideof the associated 'bladejhas a radial dimension approaching "tli'e radial Vdimension of tlieblad'e toprovide ai generous area of Contact between these partscausing vthe tapered wedgeeni gaging key to occupy 'a position Where, as a 1result -of repeated adjustment 'of the blade 'to compensate Yfor wear and grinding, `the blade no longer has restraining relationto thekey and in which the body of lthe cutter is formedwitha shallow groove `defining a restraining shoulder holding the key `in constant supporting relation tothe wedge against the contrary influences incldent to use'of Va tool of this character.

`Another object of the invention is to provide an inserted blade cutter of the type described which is of highly simplified construction, rugged and relatively cheap Vto manufacture.

Other'objects and advantages will be apparent during the courseof the following description.

YIn Athe accompanying drawing, forming 'a lpart of this application andfin which like numerals are employed to designate like parts throughout the same,

Figure 1 is a'fragmentary side elevation 'oan inserted blade cutter embodying the invention,

Figure 2 is a fragmentary group perspective of a cutting tool embodying the invention,

Figure 3 is a yperspective of a Wedge embodied in the tool, l Figure i is a sectional view taken online 4-4 of Figure 1, d ,i

l Figure 5 is aview similar Vto Figure 4, with 'the blade advanced to compensate for Wear and grinding, Y

Figure 6 isa detail transverse View taken on line 6--6 of Figure 5.

Ien-the drawing, whereinfor the purpose of illustration is shown a preferred embodiment of invention, thevnumeral 5 generally designates aarrier body. While =the body isshown 'to be of the type employed in rotary cutters, it is clear, of course, that the invention maybe carried out in other cutters. Among these might be numbered reamers, counterbores, and broaches, in 'all ot which 4my invention may be incorporated Withoutlin'ventive adaptation. n u

The body 5 is shown to' be provided with a plurality of spacedslots illopening out througlrthe peripheryN and ends loi" the body for the adjustable reception o'f blades I 2.` I

By reference tou Figure 2,v it will be seen that one sfide wall or eachs'lot and the opposed `side wail off die 'assqt'iated'bia'de sie formed with finteriitting ,serrations f4' defining 7an adjusting means and assisting in holding the blade more rigidly in a set position.

Of course, it is the back wall of each blade that is serrated while the front wall of the blade is engaged by a wedge I6. As shown in Figures l and 2, the wedge I6 is tapered radially outward and is conned between the flat front surface or wall of the blade and the converging front wall of the slot with the result that out- 10 ward movement of the wedge will force the blade laterally into binding engagement with the back wall of the slot holding the blade securely against shifting.

It is further illustrated in Figure 1, that the wedge I6 has a radial dimension approaching the corresponding dimension of the blade as initially present in the tool, producing a generous area of contact between these parts and at the same time causing the base of the wedge to be positioned close toithe inner edge of the blade as originally positioned in the tool.

Each wedge is shown to be engaged at the inner edge thereof by a longitudinally tapered key I8 driven into place from one end or side of the tool and functioning as a means to force the wedge outwardly for cooperation with the inclined front wall of the slot in forcing the wedge laterally into rm binding engagement with the complemental blade. Initially, the key I8 is overlapped by the inner portion of the associated blade and is thus held against lateral shifting by the blade but by reference to Figure 5, it will be seen that as a result of repeated adjustment of the blade to compensate for wear and grinding, the blade passes out of range of the tapered key and no longer has restraining relation thereto.

To provide for the constant holding of the key against lateral shifting regardless of the posi- 40 tion of the associated blade, the bottom of the blade and wedge receiving slot will be found to be stepped to define a shoulder 34 in constant restraining relation to the key. That is to say, the bottom of the blade and wedge receiving slot is stepped downward between the sides thereof so as to define a right angle shoulder at one side of and in direct restraining relation to the tapered key for the full length of said key and so as to maintain the key in constant supporting and bracing relation to the associated Wedge against the contrary influences known to accompany the use of tools of this type.

By reference to Figures 1 and 6 it will be seen that the inner portion of the leading side Wall of the slot I is parallel or substantially parallel to the back side Wall of the slot while the inclined portion of such leading side wall of the slot is beyond the range of the key. By this arrangement, the key is constantly spaced from the inclined portion of the leading side wall of the slot and consequently is allowed to have full and undisturbed contact with the wedge and is not forced laterally by the converging portion of the side Wall of the slot.

.65 The break in the leading side wall of the slot will be found to hold down the lateral dimension of the slot at the base portion thereof and thus avoids weakening of the body.

Figures 1, 3 and 4 illustrate that one side wall of the wedge IS is formed at what might be said to be the forward and inner corner portion thereof with a triangular relief 25 by which the Wedge is constantly spaced, in all operative positions thereof, from the radial inner portion of "76 the opposed side wall of the slot. That is to say,

the triangular relief 25 avoids contact between the inner corner of the wedge I6 and the radial or base portion of the opposed wall of the slot.

An inserted blade tool embodying the invention disclosed herein marks a definite advance over the showing in my prior patent herein identied, in that the key I8 is held in constant supporting relation to the associated wedge by the presence of the shoulder 34 while there is allowed a generous area of contact between the wedge and the blade, these matters being in contrast to the rather limited or restricted area of contact between the wedge and the blade as in my prior patent and the fact that the blade was required to remain in constant restraining relation to the associated key to hold the key in supporting engagement with the wedge.

By comparison ofthe disclosure herein with that shown on Figure 2 of my prior patent herein identified, it will be seen that in my prior patent the amount of radial blade adjustment is limited because if the blade is moved radially outward beyond the key the blade loses restraining relation to the key allowing the key to shift out of supporting engagement with the associated wedge. For this reason, the amount of expensive blade material that may be used in the previously patented cutter is limited by the necessity of maintaining the blade constantly in restraining relation to the key, while in the showing herein, the amount of expensive blade material that may be used is in no sense restricted or limited by the necessity of maintaining the blade in restraining relation to the key, it being observed in this latter connection that after the blade shown herein has been advanced to compensate for wear and grinding it no longer has restraining relation to the key, the shoulder 34 being adequate to hold the key against lateral shifting regardless of the position of the blade.

The new design of blade receiving slot as shown herein, as compared to the cross-sectional form of the blade receiving slot shown in my prior patent, is much simpler requiring fewer operations to produce the slot and simpler and less expensive tools to perform these operations. Thus, the invention herein disclosed marks an advance over the disclosure in my prior patent, herein identifled, in the provision of an inserted blade cutter in which the bottom wall of each blade receiving slot is formed immediately at the leading side of the associated blade and approximately in the plane thereof with a substantially right angle, inwardly directed step deilning a restraining shoulder in opposed spaced approximately parallel relation to the said leading side wall of the slot and constantly engaging the blade side of the key to inhibit lateral shifting of the key out of supporting relation to the wedge and to a position beneath the blade after the blade has been adjusted outward to a position where a space of a size to receive the key is left between the bottom of the blade and the bottom wall of the slot.

Having thus described the invention what is claimed is:

1. In an inserted blade cutter, a body having a slot provided with front, back and bottom walls, a wedge in the slot and positioned at the front wall thereof, a key in said slot beneath and in pressure relation to the wedge, a blade in said slot and located between the wedge and the back Wall of the slot, there being means for the outward adjustment of the blade away from the bottom wall of the slot to a point beyond said key, the bottom wall of the slot being formed with a shoulder running lengthwise of the key and engaging the blade side of the key at a point between the said front and back walls of the slot and positioned in opposed relation to the front wall of the slot and inhibiting lateral shifting of the key out of supporting relation to the wedge and to a position beneath the blade after the blade has been adjusted outward to a position where a space of a size sufficient to receive a portion of the key is left between the blade and the bottom wall of the slot.

2. In an inserted blade cutter, a body having a slot provided with a bottom wall and side walls, a blade in said slot, a wedge in said slot and located between one of said side walls and the opfrom the bottom wall of the slot to a point be-V yond said key, the bottom wall of the slotl being provided with a restraining shoulder adjacent the blade side of the key for inhibiting lateral shifting of the key out oi supporting relation to the wedge and to a position beneath the blade after the blade has been adjusted outward toa position where a space of a size sufficient to receive a portion of the key is left between the blade and the bottom wall of the slot.

FRANK P. MILLER. 

